Ph down

In the last few days I used half a bottle 250 ml of ph down in hydroponic to bring the ph down as it kept going up should I change res or is it fine

Bob999 said:

In the last few days I used half a bottle 250 ml of ph down in hydroponic to bring the ph down as it kept going up should I change res or is it fine
View attachment 5154358

Click to expand...

You need to find a stronger concentration, I use 30ml of advanced nutrients ph down per 50 gallon reservoir

Bob999 said:

In the last few days I used half a bottle 250 ml of ph down in hydroponic to bring the ph down as it kept going up should I change res or is it fine
View attachment 5154358

Click to expand...

You shouldn't be using that in a hydro res
Use phosphoric acid

You want to get a different pH down. One that's phosphoric acid is going to work better in hydro than that BioBizz citric acid.

Bob999 said:

In the last few days I used half a bottle 250 ml of ph down in hydroponic to bring the ph down as it kept going up should I change res or is it fine
View attachment 5154358

Click to expand...

What is your source water? Ppm or EC and pH?

what’s your hydro reservoir statistics?

Set at what EC/PPM and pH?

What do these numbers test at after 24 hours?

If your plants are taking up the nutrients more then the water then the pH will climb.

if You feed correctly in hydro your ppm/EC and pH should remain pretty stable.

If your nutrient concentration keeps falling in your reservoir then the pH will climb. (Feed heavier)

if your nutrient concentration keeps getting higher then the pH will fall (feeding Too heavy)

Billy the Mountain said:

You shouldn't be using that in a hydro res
Use phosphoric acid

Click to expand...

xtsho said:

You want to get a different pH down. One that's phosphoric acid is going to work better in hydro than that BioBizz citric acid.

Click to expand...

well spotted boys.

i hadn’t realised it was organic.

Thank you guys for the help appreciate that

I blame BlueLab.

calvin.m16 said:

I blame BlueLab.

Click to expand...

For sure LED too eh?

Whats wrong with blue lab what do you use ?

I quit checking pH,use much less now.

How would you know if its in suitable range

Bob999 said:

Whats wrong with blue lab what do you use ?

Click to expand...

I use General Hydroponics Drops personally but I've figured out exactly how much Potassium Silicate (PH UP) to add for my mixes so I always hit 5.8-6.0 pH, I don't have to test my PH anymore. If you're running city/well water then the quality of the water can change over time vs Reverse Osmosis or distilled water so that should be taken into consideration.

I just basically tinkered with potassium silicate (most common kind of Silica) and once I found the sweet spot around 1 oz (30ml) per/10 gallons with the brand I use I always hit 5.8-6.0 (light orange/yellow color)


I have had 3 Blue Labs pH pens in the last 2 years that have all failed with "Err" code when attempting to do the monthly calibration. I stored the pens in BlueLab KCI Storage solution and never tested plain RO or anything they advise against. The only pen of theirs that has lasted me is the pH Soil Pen which uses the BlueLab Guardian style probe.